AWS 文档 AWS SDK示例 GitHub 存储库中还有更多SDK示例
本文属于机器翻译版本。若本译文内容与英语原文存在差异,则一律以英文原文为准。
与 AWS SDK或DeleteItem
一起使用 CLI
以下代码示例演示如何使用 DeleteItem
。
操作示例是大型程序的代码摘录,必须在上下文中运行。在以下代码示例中,您可以查看此操作的上下文:
- .NET
-
- AWS SDK for .NET
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 /// <summary> /// Deletes a single item from a DynamoDB table. /// </summary> /// <param name="client">The initialized DynamoDB client object.</param> /// <param name="tableName">The name of the table from which the item /// will be deleted.</param> /// <param name="movieToDelete">A movie object containing the title and /// year of the movie to delete.</param> /// <returns>A Boolean value indicating the success or failure of the /// delete operation.</returns> public static async Task<bool> DeleteItemAsync( AmazonDynamoDBClient client, string tableName, Movie movieToDelete) { var key = new Dictionary<string, AttributeValue> { ["title"] = new AttributeValue { S = movieToDelete.Title }, ["year"] = new AttributeValue { N = movieToDelete.Year.ToString() }, }; var request = new DeleteItemRequest { TableName = tableName, Key = key, }; var response = await client.DeleteItemAsync(request); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; }
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有关API详细信息,请参阅 “AWS SDK for .NET API参考 DeleteItem” 中的。
-
- Bash
-
- AWS CLI 使用 Bash 脚本
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 ############################################################################## # function dynamodb_delete_item # # This function deletes an item from a DynamoDB table. # # Parameters: # -n table_name -- The name of the table. # -k keys -- Path to json file containing the keys that identify the item to delete. # # Returns: # 0 - If successful. # 1 - If it fails. ########################################################################### function dynamodb_delete_item() { local table_name keys response local option OPTARG # Required to use getopts command in a function. # ###################################### # Function usage explanation ####################################### function usage() { echo "function dynamodb_delete_item" echo "Delete an item from a DynamoDB table." echo " -n table_name -- The name of the table." echo " -k keys -- Path to json file containing the keys that identify the item to delete." echo "" } while getopts "n:k:h" option; do case "${option}" in n) table_name="${OPTARG}" ;; k) keys="${OPTARG}" ;; h) usage return 0 ;; \?) echo "Invalid parameter" usage return 1 ;; esac done export OPTIND=1 if [[ -z "$table_name" ]]; then errecho "ERROR: You must provide a table name with the -n parameter." usage return 1 fi if [[ -z "$keys" ]]; then errecho "ERROR: You must provide a keys json file path the -k parameter." usage return 1 fi iecho "Parameters:\n" iecho " table_name: $table_name" iecho " keys: $keys" iecho "" response=$(aws dynamodb delete-item \ --table-name "$table_name" \ --key file://"$keys") local error_code=${?} if [[ $error_code -ne 0 ]]; then aws_cli_error_log $error_code errecho "ERROR: AWS reports delete-item operation failed.$response" return 1 fi return 0 }
本示例中使用的实用程序函数。
############################################################################### # function iecho # # This function enables the script to display the specified text only if # the global variable $VERBOSE is set to true. ############################################################################### function iecho() { if [[ $VERBOSE == true ]]; then echo "$@" fi } ############################################################################### # function errecho # # This function outputs everything sent to it to STDERR (standard error output). ############################################################################### function errecho() { printf "%s\n" "$*" 1>&2 } ############################################################################## # function aws_cli_error_log() # # This function is used to log the error messages from the AWS CLI. # # See https://docs.aws.amazon.com/cli/latest/topic/return-codes.html#cli-aws-help-return-codes. # # The function expects the following argument: # $1 - The error code returned by the AWS CLI. # # Returns: # 0: - Success. # ############################################################################## function aws_cli_error_log() { local err_code=$1 errecho "Error code : $err_code" if [ "$err_code" == 1 ]; then errecho " One or more S3 transfers failed." elif [ "$err_code" == 2 ]; then errecho " Command line failed to parse." elif [ "$err_code" == 130 ]; then errecho " Process received SIGINT." elif [ "$err_code" == 252 ]; then errecho " Command syntax invalid." elif [ "$err_code" == 253 ]; then errecho " The system environment or configuration was invalid." elif [ "$err_code" == 254 ]; then errecho " The service returned an error." elif [ "$err_code" == 255 ]; then errecho " 255 is a catch-all error." fi return 0 }
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有关API详细信息,请参阅 “DeleteItem AWS CLI命令参考”。
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- C++
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- SDK对于 C++
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 //! Delete an item from an Amazon DynamoDB table. /*! \sa deleteItem() \param tableName: The table name. \param partitionKey: The partition key. \param partitionValue: The value for the partition key. \param clientConfiguration: AWS client configuration. \return bool: Function succeeded. */ bool AwsDoc::DynamoDB::deleteItem(const Aws::String &tableName, const Aws::String &partitionKey, const Aws::String &partitionValue, const Aws::Client::ClientConfiguration &clientConfiguration) { Aws::DynamoDB::DynamoDBClient dynamoClient(clientConfiguration); Aws::DynamoDB::Model::DeleteItemRequest request; request.AddKey(partitionKey, Aws::DynamoDB::Model::AttributeValue().SetS(partitionValue)); request.SetTableName(tableName); const Aws::DynamoDB::Model::DeleteItemOutcome &outcome = dynamoClient.DeleteItem( request); if (outcome.IsSuccess()) { std::cout << "Item \"" << partitionValue << "\" deleted!" << std::endl; } else { std::cerr << "Failed to delete item: " << outcome.GetError().GetMessage() << std::endl; return false; } return waitTableActive(tableName, dynamoClient); }
等待表变为活动状态的代码。
//! Query a newly created DynamoDB table until it is active. /*! \sa waitTableActive() \param waitTableActive: The DynamoDB table's name. \param dynamoClient: A DynamoDB client. \return bool: Function succeeded. */ bool AwsDoc::DynamoDB::waitTableActive(const Aws::String &tableName, const Aws::DynamoDB::DynamoDBClient &dynamoClient) { // Repeatedly call DescribeTable until table is ACTIVE. const int MAX_QUERIES = 20; Aws::DynamoDB::Model::DescribeTableRequest request; request.SetTableName(tableName); int count = 0; while (count < MAX_QUERIES) { const Aws::DynamoDB::Model::DescribeTableOutcome &result = dynamoClient.DescribeTable( request); if (result.IsSuccess()) { Aws::DynamoDB::Model::TableStatus status = result.GetResult().GetTable().GetTableStatus(); if (Aws::DynamoDB::Model::TableStatus::ACTIVE != status) { std::this_thread::sleep_for(std::chrono::seconds(1)); } else { return true; } } else { std::cerr << "Error DynamoDB::waitTableActive " << result.GetError().GetMessage() << std::endl; return false; } count++; } return false; }
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有关API详细信息,请参阅 “AWS SDK for C++ API参考 DeleteItem” 中的。
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- CLI
-
- AWS CLI
-
示例 1:删除项
以下
delete-item
示例将从MusicCollection
表中删除项,并请求有关已删除的项以及请求使用的容量的详细信息。aws dynamodb delete-item \ --table-name
MusicCollection
\ --keyfile://key.json
\ --return-valuesALL_OLD
\ --return-consumed-capacityTOTAL
\ --return-item-collection-metricsSIZE
key.json
的内容:{ "Artist": {"S": "No One You Know"}, "SongTitle": {"S": "Scared of My Shadow"} }
输出:
{ "Attributes": { "AlbumTitle": { "S": "Blue Sky Blues" }, "Artist": { "S": "No One You Know" }, "SongTitle": { "S": "Scared of My Shadow" } }, "ConsumedCapacity": { "TableName": "MusicCollection", "CapacityUnits": 2.0 }, "ItemCollectionMetrics": { "ItemCollectionKey": { "Artist": { "S": "No One You Know" } }, "SizeEstimateRangeGB": [ 0.0, 1.0 ] } }
有关更多信息,请参阅《Amazon DynamoDB 开发人员指南》中的写入项。
示例 2:有条件地删除项
以下示例仅在某项的
ProductCategory
为Sporting Goods
或Gardening Supplies
且其价格介于 500 和 600 之间时,才会将其从ProductCatalog
表中删除。它会返回有关已删除项的详细信息。aws dynamodb delete-item \ --table-name
ProductCatalog
\ --key '{"Id":{"N":"456"}}
' \ --condition-expression"(ProductCategory IN (:cat1, :cat2)) and (#P between :lo and :hi)"
\ --expression-attribute-namesfile://names.json
\ --expression-attribute-valuesfile://values.json
\ --return-valuesALL_OLD
names.json
的内容:{ "#P": "Price" }
values.json
的内容:{ ":cat1": {"S": "Sporting Goods"}, ":cat2": {"S": "Gardening Supplies"}, ":lo": {"N": "500"}, ":hi": {"N": "600"} }
输出:
{ "Attributes": { "Id": { "N": "456" }, "Price": { "N": "550" }, "ProductCategory": { "S": "Sporting Goods" } } }
有关更多信息,请参阅《Amazon DynamoDB 开发人员指南》中的写入项。
-
有关API详细信息,请参阅 “DeleteItem AWS CLI
命令参考”。
-
- Go
-
- SDK适用于 Go V2
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 // TableBasics encapsulates the Amazon DynamoDB service actions used in the examples. // It contains a DynamoDB service client that is used to act on the specified table. type TableBasics struct { DynamoDbClient *dynamodb.Client TableName string } // DeleteMovie removes a movie from the DynamoDB table. func (basics TableBasics) DeleteMovie(ctx context.Context, movie Movie) error { _, err := basics.DynamoDbClient.DeleteItem(ctx, &dynamodb.DeleteItemInput{ TableName: aws.String(basics.TableName), Key: movie.GetKey(), }) if err != nil { log.Printf("Couldn't delete %v from the table. Here's why: %v\n", movie.Title, err) } return err } // Movie encapsulates data about a movie. Title and Year are the composite primary key // of the movie in Amazon DynamoDB. Title is the sort key, Year is the partition key, // and Info is additional data. type Movie struct { Title string `dynamodbav:"title"` Year int `dynamodbav:"year"` Info map[string]interface{} `dynamodbav:"info"` } // GetKey returns the composite primary key of the movie in a format that can be // sent to DynamoDB. func (movie Movie) GetKey() map[string]types.AttributeValue { title, err := attributevalue.Marshal(movie.Title) if err != nil { panic(err) } year, err := attributevalue.Marshal(movie.Year) if err != nil { panic(err) } return map[string]types.AttributeValue{"title": title, "year": year} } // String returns the title, year, rating, and plot of a movie, formatted for the example. func (movie Movie) String() string { return fmt.Sprintf("%v\n\tReleased: %v\n\tRating: %v\n\tPlot: %v\n", movie.Title, movie.Year, movie.Info["rating"], movie.Info["plot"]) }
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有关API详细信息,请参阅 “AWS SDK for Go API参考 DeleteItem
” 中的。
-
- Java
-
- SDK适用于 Java 2.x
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.dynamodb.DynamoDbClient; import software.amazon.awssdk.services.dynamodb.model.AttributeValue; import software.amazon.awssdk.services.dynamodb.model.DeleteItemRequest; import software.amazon.awssdk.services.dynamodb.model.DynamoDbException; import java.util.HashMap; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class DeleteItem { public static void main(String[] args) { final String usage = """ Usage: <tableName> <key> <keyval> Where: tableName - The Amazon DynamoDB table to delete the item from (for example, Music3). key - The key used in the Amazon DynamoDB table (for example, Artist).\s keyval - The key value that represents the item to delete (for example, Famous Band). """; if (args.length != 3) { System.out.println(usage); System.exit(1); } String tableName = args[0]; String key = args[1]; String keyVal = args[2]; System.out.format("Deleting item \"%s\" from %s\n", keyVal, tableName); Region region = Region.US_EAST_1; DynamoDbClient ddb = DynamoDbClient.builder() .region(region) .build(); deleteDynamoDBItem(ddb, tableName, key, keyVal); ddb.close(); } public static void deleteDynamoDBItem(DynamoDbClient ddb, String tableName, String key, String keyVal) { HashMap<String, AttributeValue> keyToGet = new HashMap<>(); keyToGet.put(key, AttributeValue.builder() .s(keyVal) .build()); DeleteItemRequest deleteReq = DeleteItemRequest.builder() .tableName(tableName) .key(keyToGet) .build(); try { ddb.deleteItem(deleteReq); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } } }
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有关API详细信息,请参阅 “AWS SDK for Java 2.x API参考 DeleteItem” 中的。
-
- JavaScript
-
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 此示例使用文档客户端来简化在 DynamoDB 中处理项目的过程。有关API详细信息,请参阅DeleteCommand。
import { DynamoDBClient } from "@aws-sdk/client-dynamodb"; import { DynamoDBDocumentClient, DeleteCommand } from "@aws-sdk/lib-dynamodb"; const client = new DynamoDBClient({}); const docClient = DynamoDBDocumentClient.from(client); export const main = async () => { const command = new DeleteCommand({ TableName: "Sodas", Key: { Flavor: "Cola", }, }); const response = await docClient.send(command); console.log(response); return response; };
-
有关更多信息,请参阅 AWS SDK for JavaScript 开发人员指南。
-
有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 DeleteItem” 中的。
-
- SDK对于 JavaScript (v2)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 从表中删除项目。
// Load the AWS SDK for Node.js var AWS = require("aws-sdk"); // Set the region AWS.config.update({ region: "REGION" }); // Create the DynamoDB service object var ddb = new AWS.DynamoDB({ apiVersion: "2012-08-10" }); var params = { TableName: "TABLE", Key: { KEY_NAME: { N: "VALUE" }, }, }; // Call DynamoDB to delete the item from the table ddb.deleteItem(params, function (err, data) { if (err) { console.log("Error", err); } else { console.log("Success", data); } });
使用 DynamoDB 文档客户端从表中删除项目。
// Load the AWS SDK for Node.js var AWS = require("aws-sdk"); // Set the region AWS.config.update({ region: "REGION" }); // Create DynamoDB document client var docClient = new AWS.DynamoDB.DocumentClient({ apiVersion: "2012-08-10" }); var params = { Key: { HASH_KEY: VALUE, }, TableName: "TABLE", }; docClient.delete(params, function (err, data) { if (err) { console.log("Error", err); } else { console.log("Success", data); } });
-
有关更多信息,请参阅 AWS SDK for JavaScript 开发人员指南。
-
有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 DeleteItem” 中的。
-
- Kotlin
-
- SDK对于 Kotlin 来说
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 suspend fun deleteDynamoDBItem( tableNameVal: String, keyName: String, keyVal: String, ) { val keyToGet = mutableMapOf<String, AttributeValue>() keyToGet[keyName] = AttributeValue.S(keyVal) val request = DeleteItemRequest { tableName = tableNameVal key = keyToGet } DynamoDbClient { region = "us-east-1" }.use { ddb -> ddb.deleteItem(request) println("Item with key matching $keyVal was deleted") } }
-
有关API详细信息,请参阅DeleteItem
中的 Kotlin AWS SDK API 参考。
-
- PHP
-
- SDK for PHP
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 $key = [ 'Item' => [ 'title' => [ 'S' => $movieName, ], 'year' => [ 'N' => $movieYear, ], ] ]; $service->deleteItemByKey($tableName, $key); echo "But, bad news, this was a trap. That movie has now been deleted because of your rating...harsh.\n"; public function deleteItemByKey(string $tableName, array $key) { $this->dynamoDbClient->deleteItem([ 'Key' => $key['Item'], 'TableName' => $tableName, ]); }
-
有关API详细信息,请参阅 “AWS SDK for PHP API参考 DeleteItem” 中的。
-
- PowerShell
-
- 用于 PowerShell
-
示例 1:移除与提供的键匹配的 DynamoDB 项目。
$key = @{ SongTitle = 'Somewhere Down The Road' Artist = 'No One You Know' } | ConvertTo-DDBItem Remove-DDBItem -TableName 'Music' -Key $key -Confirm:$false
-
有关API详细信息,请参阅 AWS Tools for PowerShell Cmdlet 参考DeleteItem中的。
-
- Python
-
- SDK适用于 Python (Boto3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 class Movies: """Encapsulates an Amazon DynamoDB table of movie data. Example data structure for a movie record in this table: { "year": 1999, "title": "For Love of the Game", "info": { "directors": ["Sam Raimi"], "release_date": "1999-09-15T00:00:00Z", "rating": 6.3, "plot": "A washed up pitcher flashes through his career.", "rank": 4987, "running_time_secs": 8220, "actors": [ "Kevin Costner", "Kelly Preston", "John C. Reilly" ] } } """ def __init__(self, dyn_resource): """ :param dyn_resource: A Boto3 DynamoDB resource. """ self.dyn_resource = dyn_resource # The table variable is set during the scenario in the call to # 'exists' if the table exists. Otherwise, it is set by 'create_table'. self.table = None def delete_movie(self, title, year): """ Deletes a movie from the table. :param title: The title of the movie to delete. :param year: The release year of the movie to delete. """ try: self.table.delete_item(Key={"year": year, "title": title}) except ClientError as err: logger.error( "Couldn't delete movie %s. Here's why: %s: %s", title, err.response["Error"]["Code"], err.response["Error"]["Message"], ) raise
您可以指定条件,以便只有在项目满足特定条件时才会被删除。
class UpdateQueryWrapper: def __init__(self, table): self.table = table def delete_underrated_movie(self, title, year, rating): """ Deletes a movie only if it is rated below a specified value. By using a condition expression in a delete operation, you can specify that an item is deleted only when it meets certain criteria. :param title: The title of the movie to delete. :param year: The release year of the movie to delete. :param rating: The rating threshold to check before deleting the movie. """ try: self.table.delete_item( Key={"year": year, "title": title}, ConditionExpression="info.rating <= :val", ExpressionAttributeValues={":val": Decimal(str(rating))}, ) except ClientError as err: if err.response["Error"]["Code"] == "ConditionalCheckFailedException": logger.warning( "Didn't delete %s because its rating is greater than %s.", title, rating, ) else: logger.error( "Couldn't delete movie %s. Here's why: %s: %s", title, err.response["Error"]["Code"], err.response["Error"]["Message"], ) raise
-
有关API详细信息,请参阅DeleteItem中的 AWS SDKPython (Boto3) API 参考。
-
- Ruby
-
- SDK对于 Ruby
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 class DynamoDBBasics attr_reader :dynamo_resource, :table def initialize(table_name) client = Aws::DynamoDB::Client.new(region: 'us-east-1') @dynamo_resource = Aws::DynamoDB::Resource.new(client: client) @table = @dynamo_resource.table(table_name) end # Deletes a movie from the table. # # @param title [String] The title of the movie to delete. # @param year [Integer] The release year of the movie to delete. def delete_item(title, year) @table.delete_item(key: { 'year' => year, 'title' => title }) rescue Aws::DynamoDB::Errors::ServiceError => e puts("Couldn't delete movie #{title}. Here's why:") puts("\t#{e.code}: #{e.message}") raise end
-
有关API详细信息,请参阅 “AWS SDK for Ruby API参考 DeleteItem” 中的。
-
- Rust
-
- SDK对于 Rust
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 pub async fn delete_item( client: &Client, table: &str, key: &str, value: &str, ) -> Result<DeleteItemOutput, Error> { match client .delete_item() .table_name(table) .key(key, AttributeValue::S(value.into())) .send() .await { Ok(out) => { println!("Deleted item from table"); Ok(out) } Err(e) => Err(Error::unhandled(e)), } }
-
有关API详细信息,请参见DeleteItem
中的 Rust AWS SDK API 参考。
-
- SAP ABAP
-
- SDK对于 SAP ABAP
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 TRY. DATA(lo_resp) = lo_dyn->deleteitem( iv_tablename = iv_table_name it_key = it_key_input ). MESSAGE 'Deleted one item.' TYPE 'I'. CATCH /aws1/cx_dyncondalcheckfaile00. MESSAGE 'A condition specified in the operation could not be evaluated.' TYPE 'E'. CATCH /aws1/cx_dynresourcenotfoundex. MESSAGE 'The table or index does not exist' TYPE 'E'. CATCH /aws1/cx_dyntransactconflictex. MESSAGE 'Another transaction is using the item' TYPE 'E'. ENDTRY.
-
有关API详细信息,请参阅DeleteItem中的AWS SDK以供SAPABAPAPI参考。
-
- Swift
-
- SDK为斯威夫特
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 import AWSDynamoDB /// Delete a movie, given its title and release year. /// /// - Parameters: /// - title: The movie's title. /// - year: The movie's release year. /// func delete(title: String, year: Int) async throws { do { guard let client = self.ddbClient else { throw MoviesError.UninitializedClient } let input = DeleteItemInput( key: [ "year": .n(String(year)), "title": .s(title) ], tableName: self.tableName ) _ = try await client.deleteItem(input: input) } catch { print("ERROR: delete:", dump(error)) throw error } }
-
有关API详细信息,请参阅DeleteItem
中的 Swi AWS SDK ft API 参考。
-